中文摘要：

目的：探讨印记基因SLC22A18（solute carrier family 22,member 18）对人胶质瘤U251细胞化疗药物敏感性的影响及耐药机制的研究。方法：采用脂质体转染法将携带有SLC22A18基因的重组质粒pIRES2-EGFP-SLC22A18转入U251细胞;分别采用RT-PCR和蛋白质印迹法检测SLC22A18 mRNA及蛋白在转染后U251细胞中的表达情况;CCK-8法检测细胞对化疗药物敏感性的变化;FCM法检测SLC22A18表达对细胞凋亡以及对多柔比星在细胞内蓄积浓度的影响。结果：转染SLC22A18基因的U251细胞中有SLC22A18 mRNA及其蛋白的表达;SLC22A18基因转染组U251细胞与对照组细胞比较,U251细胞对紫杉醇的敏感性下降,半数抑制浓度（halfinhibitory concentration,IC50）值上升（t=3.23,P〈0.05）,对替莫唑胺的敏感性上升,IC50值下降（t=4.28,P〈0.05）。SLC22A18基因转染组和空质粒转染组细胞凋亡率分别为（41.35±4.98）%和（6.25±0.82）%,差异有统计学意义（t=12.05,P〈0.01）。SLC22A18表达使细胞内多柔比星蓄积浓度明显下降（t=4.25,P〈0.05）。结论：SLC22A18表达使人胶质瘤U251细胞对紫杉醇的敏感性下降,对替莫唑胺的敏感性提高,并可能通过降低细胞内化疗药物蓄积产生耐药性。

英文摘要：

Objective：To investigate the effect of imprinted SLC22A18 gene on chemotherapeutic sensitivity of U251 human glioma cells,and to explore the possible mechanism of drug-resistance.Methods：The eukaryotic expression plasmid pIRES2-EGFP-SLC22A18 was constructed and transfected into the U251 cells by liposome transfection reagent.The expression levels of SLC22A18 mRNA and protein in U251 cells were detected by RT-PCR and Western blotting,respectively.The change of sensitivity to chemotherapeutic agent for U251 cells was detected by cell counting kit-8（CCK-8） assay.The apoptosis rate and the adriamycin accumulation in the U251 cells induced by SLC22A18 expression were detected by flow cytometry（FCM）.Results：The expressions of SLC22A18 mRNA and protein were detected in the U251 cells transfected with SLC22A18 gene.As compared with the empty vector-transfected cells,the sensitivity to paclitaxel was decreased with an increased half inhibitory concentrations（IC50） value while the sensitivity to temozolomide was increased with a decreased IC50 value of the U251 cells transfected with SLC22A18 gene（t = 3.23,P0.05;t = 4.28,P0.05）.The apoptosis rates of U251 cells transfeced with SLC22A18 gene and the empty vector were（41.35 ± 4.98） % and（6.25 ± 0.82） %,respectively（t = 12.05,P0.01）.The accumulation of adriamycin in the U251 cells with SLC22A18 expression was significantly decreased（t = 4.25,P0.05）.Conclusion：The expression of SLC22A18 can reduce the sensitivity to paclitaxel and increase the sensitivity to temozolomide in U251 cells,and the drug-resistance can be induced by decreasing the accumulation of chemotherapeutic agents in U251 cells.